Robert i



R'. J. FITZGERALD CONDENSER July 14,1925. I I Re. 16,113

Original Filed Nov. 1919 INVENTOR Reissued July 14. 1925 Hes,

sonar '1. Inseam, or

New You, s. Y., assrenon or ONE-HALF 'ro J. ARTHUR rrscm,or NEW yonx, N.Y.

CONDENSER.

on mim.i,sar,s4e, dated Apri120, 1920, Serial' mi. 335374, filed mumm-4, 1919. "Application for To all whom may comm.- Be it-known that 1,ROBERT J. FITZGERALD, a citizen of the United States, and a resident ofthe boron h of Manhattan, city, wunty,

and State of ew York, have invented certain new and useful Improvementsin Condensers, of which the following is a specification. e

This invention is an improvement in condensers and has for its mainobject to provide-more eflicient and more easily applied insulationforthe condenser plates. My invention is not limited to any particularform efcondenser but possesses special adyantages in connection with acondenser of that type in which there are relatively mov-. able plateswhereby the capacity may be varie I As an important feature of myinvention I coat the various conducting elements with a non-conductingfilm permanently deposited thereon and enveloping the conductor.

- This non-conductin film, coating or jacket is preferably of sue acharacter that it is not affected by the temperature, chemical orelectric condition to which the condenser is subjected, -As an exampleof such a' film or coating I may employ an enamel composition of 'suchacharacter-that it may be baked on to the plates orother conductors.

In the accompanying drawings I haveillustrated merely one embodiment ofmyinvention and have illustratedthis on a very greatly enlarged scale,so far as the thick ness of certain of the parts is concerned, in orderto facilitate clear illustration. j c In these drawings: Figure'l is aninverted plan view; Figure 2 is a section on the line Figiire 3 isan-enlarged view of one of the elements; c g a In the form shown, thecondenser is mounted ona slab 10 of any suitable nonconducting materiaL.A plurality ofstationary condenser elements or plates '11'ofsubstantially semi-circular form are rigidly secured tosaid slab byconnecting bolts 12 or other suitable means and the plates are held inspaced relationship by spacing plu collars or strips 13. A second seriesof s11 stantially semi-circular plates 14 are connected to a shaft or,rod 15 and held in proper spaced relationship by spacers 16.

reissue filed September 21, 1920. Serial No. 411,827. c

The single rod 15 extends through the plates 14 approximately at thecenter of the curva-.

ture and is positioned-substantially at the center of the curvature ofthe stationary plates 11. Thelatter are shown as cut away, midway ofthestraight side to form a-recess 17 receiving the rod 15 and thespacers;

As previously indicated the plates are shown greatly magnified,(particularly so far as thickness is concerne The plates 11 and 14 maybe made only-approximately one hundredth (.01) of an inch in thicknessand the spacers are only of such thickness. as to permit the movableplates to freely pass between the stationary ones. With the parts in theposition shown in the drawing, the maximum surface of each plate isopposite to that of another plate, whereas by rotatingthe rod 15 bymeans of a knob or handle 18,

or other suitable means, through 180 degrees the movable plates may beentirely. I moved from between the stationary -ones' As an importantfeature" of my invention each plate has a non 'conducting coating 19thereon, the coating being of the proper ,thickness in. accordance withthe electrical pressure to which the condenser is to be subjected. Thiscoating may be of-an enamel compositionbakedon or permanently depositedthereon'but, in any event, should 7 be of such material that it will notbe affected, by and will adequately withstand temperature, chemical orelectrical conditions to whichjthe' condenser may be subjected.

means of my invention the use of separate insulation lates is avoided,each plate carries its own insulation and in case of "the breakage ofthe insulation of any late the plate'may be readil removed-an re-.placed by a new one. s previously indi- Jc'ated,I do not wish to belimited to the particular form of condenser illustrated as 7 myinvention may be applied. to various different-types, I do not'desire tobe lim ited to the small number of plates shown, as in practice a verylarge number may be used. I

Having thus 'describ'ed'my invention what I claim as new, and deshs" to''secure by Letters Patent is:

. I 1. An electric condenser including a plurality of stationaryconducting plates and,

a plurality of interposed movable plates J connected together andmovable in their own planes into and out of position between saidstationary plates, each plate having a non-conducting film or coatingdeposited on both sides thereof to inclose the plate, the coating ofeach movable plate being spaced from the coating of the adjacentstationary plate by thin air spaces. 7

2. An electric condenser including a plurality of stationary conductingplates and a plurality of interposed movab e plates connected togetherand movable in their own planes into and out of position between saidstationary plates, each plate having a nonconducting coating on bothsides thereof to inclose the plate, the coating of each movable platebeing separated from the coating of the adjacent stationary plate.

Signed at New York city, in the county of New York and State of NewYork, this 16th 20 day of September, A. D.1920.

ROBERT J. FITZGERALD.

